all: library changes for swarm-network-rewrite (#16898)

This commit adds all changes needed for the merge of swarm-network-rewrite.
The changes:

- build: increase linter timeout
- contracts/ens: export ensNode
- log: add Output method and enable fractional seconds in format
- metrics: relax test timeout
- p2p: reduced some log levels, updates to simulation packages
- rpc: increased maxClientSubscriptionBuffer to 20000

11 files changed, 481 insertions, 65 deletions

diff --git a/p2p/simulations/adapters/docker.go b/p2p/simulations/adapters/docker.go
index 8ef5629fb..d145c46b3 100644
--- a/p2p/simulations/adapters/docker.go
+++ b/p2p/simulations/adapters/docker.go
@@ -28,11 +28,14 @@ import (
 	"strings"
 
 	"github.com/docker/docker/pkg/reexec"
-	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/p2p/discover"
 )
 
+var (
+	ErrLinuxOnly = errors.New("DockerAdapter can only be used on Linux as it uses the current binary (which must be a Linux binary)")
+)
+
 // DockerAdapter is a NodeAdapter which runs simulation nodes inside Docker
 // containers.
 //
@@ -52,7 +55,7 @@ func NewDockerAdapter() (*DockerAdapter, error) {
 	// It is reasonable to require this because the caller can just
 	// compile the current binary in a Docker container.
 	if runtime.GOOS != "linux" {
-		return nil, errors.New("DockerAdapter can only be used on Linux as it uses the current binary (which must be a Linux binary)")
+		return nil, ErrLinuxOnly
 	}
 
 	if err := buildDockerImage(); err != nil {
@@ -95,7 +98,10 @@ func (d *DockerAdapter) NewNode(config *NodeConfig) (Node, error) {
 	conf.Stack.P2P.NoDiscovery = true
 	conf.Stack.P2P.NAT = nil
 	conf.Stack.NoUSB = true
-	conf.Stack.Logger = log.New("node.id", config.ID.String())
+
+	// listen on all interfaces on a given port, which we set when we
+	// initialise NodeConfig (usually a random port)
+	conf.Stack.P2P.ListenAddr = fmt.Sprintf(":%d", config.Port)
 
 	node := &DockerNode{
 		ExecNode: ExecNode{
diff --git a/p2p/simulations/adapters/exec.go b/p2p/simulations/adapters/exec.go
index f381c1159..e64cebc2a 100644
--- a/p2p/simulations/adapters/exec.go
+++ b/p2p/simulations/adapters/exec.go
@@ -17,6 +17,7 @@
 package adapters
 
 import (
+	"bufio"
 	"context"
 	"crypto/ecdsa"
 	"encoding/json"
@@ -103,9 +104,9 @@ func (e *ExecAdapter) NewNode(config *NodeConfig) (Node, error) {
 	conf.Stack.P2P.NAT = nil
 	conf.Stack.NoUSB = true
 
-	// listen on a random localhost port (we'll get the actual port after
-	// starting the node through the RPC admin.nodeInfo method)
-	conf.Stack.P2P.ListenAddr = "127.0.0.1:0"
+	// listen on a localhost port, which we set when we
+	// initialise NodeConfig (usually a random port)
+	conf.Stack.P2P.ListenAddr = fmt.Sprintf(":%d", config.Port)
 
 	node := &ExecNode{
 		ID:      config.ID,
@@ -190,9 +191,23 @@ func (n *ExecNode) Start(snapshots map[string][]byte) (err error) {
 	n.Cmd = cmd
 
 	// read the WebSocket address from the stderr logs
-	wsAddr, err := findWSAddr(stderrR, 10*time.Second)
-	if err != nil {
-		return fmt.Errorf("error getting WebSocket address: %s", err)
+	var wsAddr string
+	wsAddrC := make(chan string)
+	go func() {
+		s := bufio.NewScanner(stderrR)
+		for s.Scan() {
+			if strings.Contains(s.Text(), "WebSocket endpoint opened") {
+				wsAddrC <- wsAddrPattern.FindString(s.Text())
+			}
+		}
+	}()
+	select {
+	case wsAddr = <-wsAddrC:
+		if wsAddr == "" {
+			return errors.New("failed to read WebSocket address from stderr")
+		}
+	case <-time.After(10 * time.Second):
+		return errors.New("timed out waiting for WebSocket address on stderr")
 	}
 
 	// create the RPC client and load the node info
@@ -318,6 +333,21 @@ type execNodeConfig struct {
 	PeerAddrs map[string]string `json:"peer_addrs,omitempty"`
 }
 
+// ExternalIP gets an external IP address so that Enode URL is usable
+func ExternalIP() net.IP {
+	addrs, err := net.InterfaceAddrs()
+	if err != nil {
+		log.Crit("error getting IP address", "err", err)
+	}
+	for _, addr := range addrs {
+		if ip, ok := addr.(*net.IPNet); ok && !ip.IP.IsLoopback() && !ip.IP.IsLinkLocalUnicast() {
+			return ip.IP
+		}
+	}
+	log.Warn("unable to determine explicit IP address, falling back to loopback")
+	return net.IP{127, 0, 0, 1}
+}
+
 // execP2PNode starts a devp2p node when the current binary is executed with
 // argv[0] being "p2p-node", reading the service / ID from argv[1] / argv[2]
 // and the node config from the _P2P_NODE_CONFIG environment variable
@@ -341,25 +371,11 @@ func execP2PNode() {
 	conf.Stack.P2P.PrivateKey = conf.Node.PrivateKey
 	conf.Stack.Logger = log.New("node.id", conf.Node.ID.String())
 
-	// use explicit IP address in ListenAddr so that Enode URL is usable
-	externalIP := func() string {
-		addrs, err := net.InterfaceAddrs()
-		if err != nil {
-			log.Crit("error getting IP address", "err", err)
-		}
-		for _, addr := range addrs {
-			if ip, ok := addr.(*net.IPNet); ok && !ip.IP.IsLoopback() {
-				return ip.IP.String()
-			}
-		}
-		log.Crit("unable to determine explicit IP address")
-		return ""
-	}
 	if strings.HasPrefix(conf.Stack.P2P.ListenAddr, ":") {
-		conf.Stack.P2P.ListenAddr = externalIP() + conf.Stack.P2P.ListenAddr
+		conf.Stack.P2P.ListenAddr = ExternalIP().String() + conf.Stack.P2P.ListenAddr
 	}
 	if conf.Stack.WSHost == "0.0.0.0" {
-		conf.Stack.WSHost = externalIP()
+		conf.Stack.WSHost = ExternalIP().String()
 	}
 
 	// initialize the devp2p stack
diff --git a/p2p/simulations/adapters/inproc.go b/p2p/simulations/adapters/inproc.go
index 6d90b4a9f..b68d08f39 100644
--- a/p2p/simulations/adapters/inproc.go
+++ b/p2p/simulations/adapters/inproc.go
@@ -28,12 +28,14 @@ import (
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/p2p/discover"
+	"github.com/ethereum/go-ethereum/p2p/simulations/pipes"
 	"github.com/ethereum/go-ethereum/rpc"
 )
 
 // SimAdapter is a NodeAdapter which creates in-memory simulation nodes and
-// connects them using in-memory net.Pipe connections
+// connects them using net.Pipe
 type SimAdapter struct {
+	pipe     func() (net.Conn, net.Conn, error)
 	mtx      sync.RWMutex
 	nodes    map[discover.NodeID]*SimNode
 	services map[string]ServiceFunc
@@ -42,8 +44,18 @@ type SimAdapter struct {
 // NewSimAdapter creates a SimAdapter which is capable of running in-memory
 // simulation nodes running any of the given services (the services to run on a
 // particular node are passed to the NewNode function in the NodeConfig)
+// the adapter uses a net.Pipe for in-memory simulated network connections
 func NewSimAdapter(services map[string]ServiceFunc) *SimAdapter {
 	return &SimAdapter{
+		pipe:     pipes.NetPipe,
+		nodes:    make(map[discover.NodeID]*SimNode),
+		services: services,
+	}
+}
+
+func NewTCPAdapter(services map[string]ServiceFunc) *SimAdapter {
+	return &SimAdapter{
+		pipe:     pipes.TCPPipe,
 		nodes:    make(map[discover.NodeID]*SimNode),
 		services: services,
 	}
@@ -81,7 +93,7 @@ func (s *SimAdapter) NewNode(config *NodeConfig) (Node, error) {
 			MaxPeers:        math.MaxInt32,
 			NoDiscovery:     true,
 			Dialer:          s,
-			EnableMsgEvents: true,
+			EnableMsgEvents: config.EnableMsgEvents,
 		},
 		NoUSB:  true,
 		Logger: log.New("node.id", id.String()),
@@ -102,7 +114,7 @@ func (s *SimAdapter) NewNode(config *NodeConfig) (Node, error) {
 }
 
 // Dial implements the p2p.NodeDialer interface by connecting to the node using
-// an in-memory net.Pipe connection
+// an in-memory net.Pipe
 func (s *SimAdapter) Dial(dest *discover.Node) (conn net.Conn, err error) {
 	node, ok := s.GetNode(dest.ID)
 	if !ok {
@@ -112,7 +124,14 @@ func (s *SimAdapter) Dial(dest *discover.Node) (conn net.Conn, err error) {
 	if srv == nil {
 		return nil, fmt.Errorf("node not running: %s", dest.ID)
 	}
-	pipe1, pipe2 := net.Pipe()
+	// SimAdapter.pipe is net.Pipe (NewSimAdapter)
+	pipe1, pipe2, err := s.pipe()
+	if err != nil {
+		return nil, err
+	}
+	// this is simulated 'listening'
+	// asynchronously call the dialed destintion node's p2p server
+	// to set up connection on the 'listening' side
 	go srv.SetupConn(pipe1, 0, nil)
 	return pipe2, nil
 }
@@ -140,8 +159,8 @@ func (s *SimAdapter) GetNode(id discover.NodeID) (*SimNode, bool) {
 }
 
 // SimNode is an in-memory simulation node which connects to other nodes using
-// an in-memory net.Pipe connection (see SimAdapter.Dial), running devp2p
-// protocols directly over that pipe
+// net.Pipe (see SimAdapter.Dial), running devp2p protocols directly over that
+// pipe
 type SimNode struct {
 	lock         sync.RWMutex
 	ID           discover.NodeID
@@ -241,7 +260,7 @@ func (sn *SimNode) Start(snapshots map[string][]byte) error {
 		for _, name := range sn.config.Services {
 			if err := sn.node.Register(newService(name)); err != nil {
 				regErr = err
-				return
+				break
 			}
 		}
 	})
@@ -314,3 +333,18 @@ func (sn *SimNode) NodeInfo() *p2p.NodeInfo {
 	}
 	return server.NodeInfo()
 }
+
+func setSocketBuffer(conn net.Conn, socketReadBuffer int, socketWriteBuffer int) error {
+	switch v := conn.(type) {
+	case *net.UnixConn:
+		err := v.SetReadBuffer(socketReadBuffer)
+		if err != nil {
+			return err
+		}
+		err = v.SetWriteBuffer(socketWriteBuffer)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
diff --git a/p2p/simulations/adapters/inproc_test.go b/p2p/simulations/adapters/inproc_test.go
new file mode 100644
index 000000000..e1e092f6e
--- /dev/null
+++ b/p2p/simulations/adapters/inproc_test.go
@@ -0,0 +1,259 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package adapters
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/ethereum/go-ethereum/p2p/simulations/pipes"
+)
+
+func TestTCPPipe(t *testing.T) {
+	c1, c2, err := pipes.TCPPipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	done := make(chan struct{})
+
+	go func() {
+		msgs := 50
+		size := 1024
+		for i := 0; i < msgs; i++ {
+			msg := make([]byte, size)
+			_ = binary.PutUvarint(msg, uint64(i))
+
+			_, err := c1.Write(msg)
+			if err != nil {
+				t.Fatal(err)
+			}
+		}
+
+		for i := 0; i < msgs; i++ {
+			msg := make([]byte, size)
+			_ = binary.PutUvarint(msg, uint64(i))
+
+			out := make([]byte, size)
+			_, err := c2.Read(out)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if !bytes.Equal(msg, out) {
+				t.Fatalf("expected %#v, got %#v", msg, out)
+			}
+		}
+		done <- struct{}{}
+	}()
+
+	select {
+	case <-done:
+	case <-time.After(5 * time.Second):
+		t.Fatal("test timeout")
+	}
+}
+
+func TestTCPPipeBidirections(t *testing.T) {
+	c1, c2, err := pipes.TCPPipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	done := make(chan struct{})
+
+	go func() {
+		msgs := 50
+		size := 7
+		for i := 0; i < msgs; i++ {
+			msg := []byte(fmt.Sprintf("ping %02d", i))
+
+			_, err := c1.Write(msg)
+			if err != nil {
+				t.Fatal(err)
+			}
+		}
+
+		for i := 0; i < msgs; i++ {
+			expected := []byte(fmt.Sprintf("ping %02d", i))
+
+			out := make([]byte, size)
+			_, err := c2.Read(out)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if !bytes.Equal(expected, out) {
+				t.Fatalf("expected %#v, got %#v", out, expected)
+			} else {
+				msg := []byte(fmt.Sprintf("pong %02d", i))
+				_, err := c2.Write(msg)
+				if err != nil {
+					t.Fatal(err)
+				}
+			}
+		}
+
+		for i := 0; i < msgs; i++ {
+			expected := []byte(fmt.Sprintf("pong %02d", i))
+
+			out := make([]byte, size)
+			_, err := c1.Read(out)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if !bytes.Equal(expected, out) {
+				t.Fatalf("expected %#v, got %#v", out, expected)
+			}
+		}
+		done <- struct{}{}
+	}()
+
+	select {
+	case <-done:
+	case <-time.After(5 * time.Second):
+		t.Fatal("test timeout")
+	}
+}
+
+func TestNetPipe(t *testing.T) {
+	c1, c2, err := pipes.NetPipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	done := make(chan struct{})
+
+	go func() {
+		msgs := 50
+		size := 1024
+		// netPipe is blocking, so writes are emitted asynchronously
+		go func() {
+			for i := 0; i < msgs; i++ {
+				msg := make([]byte, size)
+				_ = binary.PutUvarint(msg, uint64(i))
+
+				_, err := c1.Write(msg)
+				if err != nil {
+					t.Fatal(err)
+				}
+			}
+		}()
+
+		for i := 0; i < msgs; i++ {
+			msg := make([]byte, size)
+			_ = binary.PutUvarint(msg, uint64(i))
+
+			out := make([]byte, size)
+			_, err := c2.Read(out)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if !bytes.Equal(msg, out) {
+				t.Fatalf("expected %#v, got %#v", msg, out)
+			}
+		}
+
+		done <- struct{}{}
+	}()
+
+	select {
+	case <-done:
+	case <-time.After(5 * time.Second):
+		t.Fatal("test timeout")
+	}
+}
+
+func TestNetPipeBidirections(t *testing.T) {
+	c1, c2, err := pipes.NetPipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	done := make(chan struct{})
+
+	go func() {
+		msgs := 1000
+		size := 8
+		pingTemplate := "ping %03d"
+		pongTemplate := "pong %03d"
+
+		// netPipe is blocking, so writes are emitted asynchronously
+		go func() {
+			for i := 0; i < msgs; i++ {
+				msg := []byte(fmt.Sprintf(pingTemplate, i))
+
+				_, err := c1.Write(msg)
+				if err != nil {
+					t.Fatal(err)
+				}
+			}
+		}()
+
+		// netPipe is blocking, so reads for pong are emitted asynchronously
+		go func() {
+			for i := 0; i < msgs; i++ {
+				expected := []byte(fmt.Sprintf(pongTemplate, i))
+
+				out := make([]byte, size)
+				_, err := c1.Read(out)
+				if err != nil {
+					t.Fatal(err)
+				}
+
+				if !bytes.Equal(expected, out) {
+					t.Fatalf("expected %#v, got %#v", expected, out)
+				}
+			}
+
+			done <- struct{}{}
+		}()
+
+		// expect to read pings, and respond with pongs to the alternate connection
+		for i := 0; i < msgs; i++ {
+			expected := []byte(fmt.Sprintf(pingTemplate, i))
+
+			out := make([]byte, size)
+			_, err := c2.Read(out)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if !bytes.Equal(expected, out) {
+				t.Fatalf("expected %#v, got %#v", expected, out)
+			} else {
+				msg := []byte(fmt.Sprintf(pongTemplate, i))
+
+				_, err := c2.Write(msg)
+				if err != nil {
+					t.Fatal(err)
+				}
+			}
+		}
+	}()
+
+	select {
+	case <-done:
+	case <-time.After(5 * time.Second):
+		t.Fatal("test timeout")
+	}
+}
diff --git a/p2p/simulations/adapters/types.go b/p2p/simulations/adapters/types.go
index 5b4b47fe2..2c4b9dd8f 100644
--- a/p2p/simulations/adapters/types.go
+++ b/p2p/simulations/adapters/types.go
@@ -23,6 +23,7 @@ import (
 	"fmt"
 	"net"
 	"os"
+	"strconv"
 
 	"github.com/docker/docker/pkg/reexec"
 	"github.com/ethereum/go-ethereum/crypto"
@@ -97,24 +98,30 @@ type NodeConfig struct {
 
 	// function to sanction or prevent suggesting a peer
 	Reachable func(id discover.NodeID) bool
+
+	Port uint16
 }
 
 // nodeConfigJSON is used to encode and decode NodeConfig as JSON by encoding
 // all fields as strings
 type nodeConfigJSON struct {
-	ID         string   `json:"id"`
-	PrivateKey string   `json:"private_key"`
-	Name       string   `json:"name"`
-	Services   []string `json:"services"`
+	ID              string   `json:"id"`
+	PrivateKey      string   `json:"private_key"`
+	Name            string   `json:"name"`
+	Services        []string `json:"services"`
+	EnableMsgEvents bool     `json:"enable_msg_events"`
+	Port            uint16   `json:"port"`
 }
 
 // MarshalJSON implements the json.Marshaler interface by encoding the config
 // fields as strings
 func (n *NodeConfig) MarshalJSON() ([]byte, error) {
 	confJSON := nodeConfigJSON{
-		ID:       n.ID.String(),
-		Name:     n.Name,
-		Services: n.Services,
+		ID:              n.ID.String(),
+		Name:            n.Name,
+		Services:        n.Services,
+		Port:            n.Port,
+		EnableMsgEvents: n.EnableMsgEvents,
 	}
 	if n.PrivateKey != nil {
 		confJSON.PrivateKey = hex.EncodeToString(crypto.FromECDSA(n.PrivateKey))
@@ -152,6 +159,8 @@ func (n *NodeConfig) UnmarshalJSON(data []byte) error {
 
 	n.Name = confJSON.Name
 	n.Services = confJSON.Services
+	n.Port = confJSON.Port
+	n.EnableMsgEvents = confJSON.EnableMsgEvents
 
 	return nil
 }
@@ -163,13 +172,36 @@ func RandomNodeConfig() *NodeConfig {
 	if err != nil {
 		panic("unable to generate key")
 	}
-	var id discover.NodeID
-	pubkey := crypto.FromECDSAPub(&key.PublicKey)
-	copy(id[:], pubkey[1:])
+
+	id := discover.PubkeyID(&key.PublicKey)
+	port, err := assignTCPPort()
+	if err != nil {
+		panic("unable to assign tcp port")
+	}
 	return &NodeConfig{
-		ID:         id,
-		PrivateKey: key,
+		ID:              id,
+		Name:            fmt.Sprintf("node_%s", id.String()),
+		PrivateKey:      key,
+		Port:            port,
+		EnableMsgEvents: true,
+	}
+}
+
+func assignTCPPort() (uint16, error) {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		return 0, err
+	}
+	l.Close()
+	_, port, err := net.SplitHostPort(l.Addr().String())
+	if err != nil {
+		return 0, err
+	}
+	p, err := strconv.ParseInt(port, 10, 32)
+	if err != nil {
+		return 0, err
 	}
+	return uint16(p), nil
 }
 
 // ServiceContext is a collection of options and methods which can be utilised
diff --git a/p2p/simulations/http.go b/p2p/simulations/http.go
index 97dd742e8..24001f194 100644
--- a/p2p/simulations/http.go
+++ b/p2p/simulations/http.go
@@ -561,7 +561,8 @@ func (s *Server) LoadSnapshot(w http.ResponseWriter, req *http.Request) {
 
 // CreateNode creates a node in the network using the given configuration
 func (s *Server) CreateNode(w http.ResponseWriter, req *http.Request) {
-	config := adapters.RandomNodeConfig()
+	config := &adapters.NodeConfig{}
+
 	err := json.NewDecoder(req.Body).Decode(config)
 	if err != nil && err != io.EOF {
 		http.Error(w, err.Error(), http.StatusBadRequest)
diff --git a/p2p/simulations/http_test.go b/p2p/simulations/http_test.go
index 677a8fb14..732d49f54 100644
--- a/p2p/simulations/http_test.go
+++ b/p2p/simulations/http_test.go
@@ -348,7 +348,8 @@ func startTestNetwork(t *testing.T, client *Client) []string {
 	nodeCount := 2
 	nodeIDs := make([]string, nodeCount)
 	for i := 0; i < nodeCount; i++ {
-		node, err := client.CreateNode(nil)
+		config := adapters.RandomNodeConfig()
+		node, err := client.CreateNode(config)
 		if err != nil {
 			t.Fatalf("error creating node: %s", err)
 		}
@@ -527,7 +528,9 @@ func TestHTTPNodeRPC(t *testing.T) {
 
 	// start a node in the network
 	client := NewClient(s.URL)
-	node, err := client.CreateNode(nil)
+
+	config := adapters.RandomNodeConfig()
+	node, err := client.CreateNode(config)
 	if err != nil {
 		t.Fatalf("error creating node: %s", err)
 	}
@@ -589,7 +592,8 @@ func TestHTTPSnapshot(t *testing.T) {
 	nodeCount := 2
 	nodes := make([]*p2p.NodeInfo, nodeCount)
 	for i := 0; i < nodeCount; i++ {
-		node, err := client.CreateNode(nil)
+		config := adapters.RandomNodeConfig()
+		node, err := client.CreateNode(config)
 		if err != nil {
 			t.Fatalf("error creating node: %s", err)
 		}
diff --git a/p2p/simulations/mocker.go b/p2p/simulations/mocker.go
index c38e28855..389b1e3ec 100644
--- a/p2p/simulations/mocker.go
+++ b/p2p/simulations/mocker.go
@@ -26,6 +26,7 @@ import (
 
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p/discover"
+	"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
 )
 
 //a map of mocker names to its function
@@ -102,7 +103,13 @@ func startStop(net *Network, quit chan struct{}, nodeCount int) {
 func probabilistic(net *Network, quit chan struct{}, nodeCount int) {
 	nodes, err := connectNodesInRing(net, nodeCount)
 	if err != nil {
-		panic("Could not startup node network for mocker")
+		select {
+		case <-quit:
+			//error may be due to abortion of mocking; so the quit channel is closed
+			return
+		default:
+			panic("Could not startup node network for mocker")
+		}
 	}
 	for {
 		select {
@@ -143,7 +150,7 @@ func probabilistic(net *Network, quit chan struct{}, nodeCount int) {
 			log.Debug(fmt.Sprintf("node %v shutting down", nodes[i]))
 			err := net.Stop(nodes[i])
 			if err != nil {
-				log.Error(fmt.Sprintf("Error stopping node %s", nodes[i]))
+				log.Error("Error stopping node", "node", nodes[i])
 				wg.Done()
 				continue
 			}
@@ -151,7 +158,7 @@ func probabilistic(net *Network, quit chan struct{}, nodeCount int) {
 				time.Sleep(randWait)
 				err := net.Start(id)
 				if err != nil {
-					log.Error(fmt.Sprintf("Error starting node %s", id))
+					log.Error("Error starting node", "node", id)
 				}
 				wg.Done()
 			}(nodes[i])
@@ -165,9 +172,10 @@ func probabilistic(net *Network, quit chan struct{}, nodeCount int) {
 func connectNodesInRing(net *Network, nodeCount int) ([]discover.NodeID, error) {
 	ids := make([]discover.NodeID, nodeCount)
 	for i := 0; i < nodeCount; i++ {
-		node, err := net.NewNode()
+		conf := adapters.RandomNodeConfig()
+		node, err := net.NewNodeWithConfig(conf)
 		if err != nil {
-			log.Error("Error creating a node! %s", err)
+			log.Error("Error creating a node!", "err", err)
 			return nil, err
 		}
 		ids[i] = node.ID()
@@ -175,7 +183,7 @@ func connectNodesInRing(net *Network, nodeCount int) ([]discover.NodeID, error)
 
 	for _, id := range ids {
 		if err := net.Start(id); err != nil {
-			log.Error("Error starting a node! %s", err)
+			log.Error("Error starting a node!", "err", err)
 			return nil, err
 		}
 		log.Debug(fmt.Sprintf("node %v starting up", id))
@@ -183,7 +191,7 @@ func connectNodesInRing(net *Network, nodeCount int) ([]discover.NodeID, error)
 	for i, id := range ids {
 		peerID := ids[(i+1)%len(ids)]
 		if err := net.Connect(id, peerID); err != nil {
-			log.Error("Error connecting a node to a peer! %s", err)
+			log.Error("Error connecting a node to a peer!", "err", err)
 			return nil, err
 		}
 	}
diff --git a/p2p/simulations/network.go b/p2p/simulations/network.go
index 1a2c1e8ff..a8a46cd87 100644
--- a/p2p/simulations/network.go
+++ b/p2p/simulations/network.go
@@ -382,6 +382,15 @@ func (net *Network) GetNodeByName(name string) *Node {
 	return net.getNodeByName(name)
 }
 
+// GetNodes returns the existing nodes
+func (net *Network) GetNodes() (nodes []*Node) {
+	net.lock.Lock()
+	defer net.lock.Unlock()
+
+	nodes = append(nodes, net.Nodes...)
+	return nodes
+}
+
 func (net *Network) getNode(id discover.NodeID) *Node {
 	i, found := net.nodeMap[id]
 	if !found {
@@ -399,15 +408,6 @@ func (net *Network) getNodeByName(name string) *Node {
 	return nil
 }
 
-// GetNodes returns the existing nodes
-func (net *Network) GetNodes() (nodes []*Node) {
-	net.lock.Lock()
-	defer net.lock.Unlock()
-
-	nodes = append(nodes, net.Nodes...)
-	return nodes
-}
-
 // GetConn returns the connection which exists between "one" and "other"
 // regardless of which node initiated the connection
 func (net *Network) GetConn(oneID, otherID discover.NodeID) *Conn {
diff --git a/p2p/simulations/network_test.go b/p2p/simulations/network_test.go
index 2a062121b..f178bac50 100644
--- a/p2p/simulations/network_test.go
+++ b/p2p/simulations/network_test.go
@@ -41,7 +41,8 @@ func TestNetworkSimulation(t *testing.T) {
 	nodeCount := 20
 	ids := make([]discover.NodeID, nodeCount)
 	for i := 0; i < nodeCount; i++ {
-		node, err := network.NewNode()
+		conf := adapters.RandomNodeConfig()
+		node, err := network.NewNodeWithConfig(conf)
 		if err != nil {
 			t.Fatalf("error creating node: %s", err)
 		}
diff --git a/p2p/simulations/pipes/pipes.go b/p2p/simulations/pipes/pipes.go
new file mode 100644
index 000000000..8532c1bcf
--- /dev/null
+++ b/p2p/simulations/pipes/pipes.go
@@ -0,0 +1,55 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package pipes
+
+import (
+	"net"
+)
+
+// NetPipe wraps net.Pipe in a signature returning an error
+func NetPipe() (net.Conn, net.Conn, error) {
+	p1, p2 := net.Pipe()
+	return p1, p2, nil
+}
+
+// TCPPipe creates an in process full duplex pipe based on a localhost TCP socket
+func TCPPipe() (net.Conn, net.Conn, error) {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		return nil, nil, err
+	}
+	defer l.Close()
+
+	var aconn net.Conn
+	aerr := make(chan error, 1)
+	go func() {
+		var err error
+		aconn, err = l.Accept()
+		aerr <- err
+	}()
+
+	dconn, err := net.Dial("tcp", l.Addr().String())
+	if err != nil {
+		<-aerr
+		return nil, nil, err
+	}
+	if err := <-aerr; err != nil {
+		dconn.Close()
+		return nil, nil, err
+	}
+	return aconn, dconn, nil
+}